The present invention relates to a flow meter which will allow determination of density, flow rate, and viscosity of a conceptually incompressible fluid from pressure drop measurements alone.
The flow meters presently available are generally restricted to use with a particular fluid or fluid type or are limited to measuring only one of the three important flow parameters, namely density, flow rate and viscosity.
An example of the prior art can be found in U.S. Pat. No. 3,839,914 which discloses a method and apparatus for continuously determining density, velocity and Fanning friction factor, which is further used to determine the viscosity of a liquid flowing through a closed container. The liquid is caused to flow through a conduit having a curved portion and pressure sensors are mounted on both sides of the curved portion to determine the difference in pressure between the fluid flowing adjacent to the inside and the outside curved portion of the conduit. Further pressure sensors are positioned in the conduit at selected equal distances up stream and downstream of the sensors located in the curved portion of the conduit. The difference in pressure of the fluid between these upstream and downstream locations and between the upstream and downstream locations and the curved portion of the conduit are determined. These pressure determinations are then utilized in equations to determine the desired parameters of density, flow velocity and Fanning friction factor.